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Help With Boiler Leak

STvexSTvex Member Posts: 38

I just noticed a small leak coming from the bottom of my boiler. I have a weil eg-45 gas steam boiler about 31 years old. The leak is coming from the back left side. I attached three pictures. One of the leak, the second the back and third the underside. The underside picture is upside down. I can't seem to figure out where the leak is coming from. I took the front cover off and looked where the burner is but I don't see any water dripping from the bottom of the boiler chest, I took the back cover off and don't see water leaking either. But when I put my finger where the towel is, I can feel water. I've been placing new paper towels a few times already and they come out wet. Can any of you guys tell where the leak is coming from? I was thinking of adding two quarts of the boiler leak sealer that they sell at the big box stores, run the boiler a few times and let the water sit to see if it still leaks. Do those products work? Other than replacing the boiler, what other options do I have? Thanks in advance for the help.


  • JStarJStar Member Posts: 2,752
    It's probably leaking from above the water line. The leak-sealer may work for a week or two but not permanently. You'll be better off replacing that whole boiler.
  • nicholas bonham-carternicholas bonham-carter Member Posts: 8,137
    edited May 2015
    Overfill the boiler, until you can feel the header get cold from the water, and let it sit for a few hours. During this time you should see where the leak is.
    Stop leak will not be a permanent solution. You have time now to do a thorough examination, and planning for the replacement.
    Don't forget to measure the radiators for the sizing of the boiler-do not simply choose one of the same size as you now have, as it may have been incorrectly chosen.--NBC
  • STvexSTvex Member Posts: 38
    Thanks I will try that, where can I get edr charts for my radiators? Can I go by square foot of house then calculate boiler gross btu?
  • Jamie HallJamie Hall Member Posts: 12,947
    STvex said:

    Thanks I will try that, where can I get edr charts for my radiators? Can I go by square foot of house then calculate boiler gross btu?

    No, you can't. Steam boilers are sized by the connected radiation ("EDR"), not the size of the house or the heat loss!

    There are tables showing the EDR of various radiators in the reference section of this site.
    Br. Jamie, osb

    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England.

    Hoffman Equipped System (all original except boiler), Weil-Mclain 580, 2.75 gph Carlin, Vapourstat 0.5 -- 6.0 ounces per square inch
  • STvexSTvex Member Posts: 38
    Thanks Ill look for the charts
  • STvexSTvex Member Posts: 38
    Thanks Fred great reference, saved me a lot of time
  • JStarJStar Member Posts: 2,752
    The charts from Columbia can be off by 20% from what I've seen. Try these charts, too.
  • STvexSTvex Member Posts: 38
    Thanks jstar
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